VMware RDMs in Physical Vs Virtual compatibility mode

Behaves exactly like a virtual disk & Guest OS sees it as a virtual disk and the real characteristics are hidden.

RDM behaves as a virtual disk

Allows the Guest OS to access the hardware directly.

Luns with size limit of 2tb for RDMs

Luns of size greater than 2tb are supported

A disk device backed by a virtualcompatibility mode raw disk mapping can use disk modes.

A disk device backed by a physical compatibility mode raw disk mapping cannot use disk modes, and commands are passed straight through to the LUN indicated by the raw disk mapping.

Doesn’t support MSCS (Microsoft clustering services)

Supports MSCS (Microsoft clustering services

For virtualcompatibility mode RDMs, you can migrate the mapping file or convert to thick-provisioned or thin-provisioned disks during migration as long as the destination is not an NFS datastore. If you convert the mapping file, a new virtual disk is created and the contents of the mapped LUN are copied to this disk

For physical compatibility mode RDMs, you can migrate the mapping file only.

Bad for SAN aware applications.

Best for SAN aware applications.

Cloning is possible

No

Create templates of the VM with RDMs in virtual compatibility mode.

No

During migration you can either migrate the mapping file or copy the contents of the RDM lun into a virtual disk.

About Me

A passionate IT Professional with an endless fetish for innovative Science & Technology.I am a lot of things and a few among them areAn avid gamer,loves photography(not anymore),love a lot of variety of music, movies (foreign),like a lot of manga, anime series and most importantly love life.